Stent

Abstract

A stent includes linear struts that form an outer periphery of a cylindrical shape in which a gap is formed between adjacent struts. Each strut has a first convex portion that protrudes inward in a radial direction R in at least a portion in a cross section along an axial direction of the cylindrical shape, and, in a state in which the stent is indwelled in a lumen in a living body, the first convex portion has a vertex that is formed to be positioned more on an upstream side of blood flow than a downstream side of blood flow and an upstream curved portion that curves and extends to protrude inward in the radial direction from the vertex toward the upstream side.

What is claimed is: 
     
         1 . A stent comprising:
 a plurality of linear struts that form an outer periphery of a cylindrical shape in which a gap is formed between adjacent ones of the plurality of linear struts,   wherein, in a cross section along an axial direction of the cylindrical shape, each strut has a convex portion that protrudes inward in a radial direction in at least a portion of the strut, and   wherein, in a state in which the stent is indwelled in a lumen in a living body,   the convex portion includes:   a vertex that is formed to be positioned more on an upstream side of blood flow than a downstream side of blood flow, and   an upstream curved portion that curves and extends to protrude inward in the radial direction from the vertex toward the upstream side.   
     
     
         2 . The stent according to  claim 1 ,
 wherein, in the cross section along the axial direction, the convex portion further includes a downstream curved portion provided on the downstream side from the vertex and that curves and extends to protrude inward in the radial direction.   
     
     
         3 . The stent according to  claim 2 ,
 wherein, in the cross section along the axial direction, the convex portion is configured so that a ratio of a length along the axial direction from an upstream edge of the convex portion to the vertex and a length along the axial direction from a downstream edge of the convex portion to the vertex is within a range of 1:7 to 3:5.   
     
     
         4 . The stent according to  claim 3 ,
 wherein, in the cross section along the axial direction, the convex portion further includes a linear portion that interlocks the upstream curved portion and the downstream curved portion and is provided along a tangent line at the vertex of the upstream curved portion.   
     
     
         5 . The stent according to  claim 4 ,
 wherein, in the cross section along the axial direction, the convex portion further includes an upstream continuous portion that is continuous from an end portion on the upstream side in the upstream curved portion to the upstream edge of the convex portion and curves to be recessed outward in the radial direction, and   a downstream continuous portion that is continuous from an end portion on the downstream side in the downstream curved portion to the downstream edge of the convex portion and curves to be recessed outward in the radial direction.   
     
     
         6 . The stent according to  claim 1 , further comprising:
 a plurality of link portions that connects the plurality of struts to each other, the plurality of link portions being disposed in the gap between adjacent ones of the plurality of struts,   wherein each strut has a plurality of main strut portions and a plurality of bent portions that interlocks the main strut portions that extend in different directions, and   wherein at least one of the plurality of link portions and/or at least one of the plurality of bent portions includes the convex portion.   
     
     
         7 . The stent according to  claim 1 , wherein the stent is manufactured by injection molding or laminate molding. 
     
     
         8 . A stent comprising:
 a plurality of linear struts that form an outer periphery of a cylindrical shape in which a gap is formed between adjacent ones of the plurality of struts,   wherein, in a cross section along an axial direction of the cylindrical shape of the strut, the strut includes a convex portion defined by:   an outer peripheral distal end point and an outer periphery proximal end point on an outer peripheral side of a cylinder,   an inner peripheral distal end point and an inner periphery proximal end point on an inner peripheral side of a cylinder,   an outer peripheral linear portion that interlocks the outer peripheral distal end point and the outer periphery proximal end point,   an inner peripheral linear portion that interlocks the inner peripheral distal end point and the inner periphery proximal end point,   a distal end curved portion that smoothly interlocks the outer peripheral distal end point and the inner peripheral distal end point, and   a proximal end curved portion that smoothly interlocks the outer periphery proximal end point and the inner periphery proximal end point.   
     
     
         9 . The stent according to  claim 8 , wherein the distal end curved portion includes an upstream curved portion that curves and extends to protrude inward in the radial direction from the outer peripheral distal end point toward the upstream side and an upstream continuous portion that is continuous from an end portion on the upstream side of the upstream curved portion to the inner peripheral distal end point and curves to be recessed outward in the radial direction. 
     
     
         10 . The stent according to  claim 8 , wherein the proximal end curved portion includes a downstream curved portion that is provided on the downstream side from the outer periphery proximal end point and that curves and extends to protrude inward in the radial direction and a downstream continuous portion that is continuous from an end portion on the downstream side in the downstream curved portion to the inner periphery proximal end point and curves to be recessed outward in the radial direction. 
     
     
         11 . The stent according to  claim 8 , further comprising:
 a plurality of link portions that connects the plurality of struts to each other, the plurality of link portions being disposed in the gap between adjacent ones of the plurality of struts,   wherein each strut has a plurality of main strut portions and a plurality of bent portions that interlocks the main strut portions that extend in different directions, and   wherein at least one of the plurality of link portions and/or at least one of the plurality of bent portions includes the convex portion.   
     
     
         12 . A stent comprising:
 a plurality of linear struts that form an outer periphery of a cylindrical shape in which a gap is formed between adjacent said linear struts,   wherein, in a cross section along an axial direction of the cylindrical shape of the strut, the strut includes a convex portion defined by:   an outer peripheral distal end point and an outer periphery proximal end point on an outer peripheral side of a cylinder,   an inner peripheral distal end point and an inner periphery proximal end point on an inner peripheral side of a cylinder,   an outer peripheral linear portion that interlocks the outer peripheral distal end point and the outer periphery proximal end point,   an inner peripheral linear portion that interlocks the inner peripheral distal end point and the inner periphery proximal end point,   a distal end curved portion that interlocks the outer peripheral distal end point and the inner peripheral distal end point, and   a proximal end curved portion that smoothly interlocks the outer periphery proximal end point and the inner periphery proximal end point, and   wherein a ratio of a length along the axial direction from the outer peripheral distal end point to the inner peripheral distal end point and a length along the axial direction from the inner peripheral distal end point to the outer periphery proximal end point is within a range of 1:7 to 3:5.   
     
     
         13 . The stent according to  claim 12 , wherein the proximal end curved portion includes a downstream curved portion that is provided on the downstream side from the outer periphery proximal end point and that curves and extends to protrude inward in the radial direction and a downstream continuous portion that is continuous from an end portion on the downstream side in the downstream curved portion to the inner periphery proximal end point and curves to be recessed outward in the radial direction. 
     
     
         14 . The stent according to  claim 12 , further comprising:
 a plurality of link portions that connects the plurality of struts to each other, the plurality of link portions being disposed in the gap between adjacent ones of the plurality of struts,   wherein each strut has a plurality of main strut portions and a plurality of bent portions that interlocks the main strut portions that extend in different directions, and   wherein at least one of the plurality of link portions and/or at least one of the plurality of bent portions includes the convex portion.